Deep inside the highly fortified Green Zone in Baghdad, politics feels a world away from the feverish mood in Washington.

"The political system is completely paralysed," says Ala Abdul Razzak from the Tawafuq Front, the main Sunni group boycotting both the cabinet and the parliament.

"Either the government is unable to do anything, or they want it to be like this. The end result is - we are not moving."

The parliament has not been sitting for most of this week. Its members plan to take the whole of August off.

Two influential Sunni and Shia groups refuse to sit in the chamber. They are also boycotting cabinet meetings.

The impression at the moment is of a political system that is barely functioning. This is all deeply frustrating for US commanders here, and policy makers back in Washington.

Different priorities

One of the main aims of the surge in US troops was to give Iraqi politicians the space to pass a series of important laws - on sharing oil resources, constitutional reform and giving jobs to former members of Saddam Hussein's Baath party.

We don't work here on what the opinion is in Washington

Layla al-Khafajii, deputy, Shia Alliance

These are among the benchmarks against which progress in Iraq is being measured.

Even if the 30,000 extra US troops manage to reduce the violence, the surge could still be judged a failure.

Many here think long-term stability will only be achieved if there i' much faster political reconciliation.

Some members of the Iraqi parliament, though, do not want to be seen to be responding to pressure from the United States.

"We don't work here on what the opinion is in Washington," says Layla al-Khafajii from the Shia Alliance. "What happens in Washington is something they have to deal with, not us. What affects us is what our people on the streets are thinking."

She thinks progress is possible in the weeks ahead, and says Iraqis have now made the choice to embrace democracy. There is no going back, she says, despite the difficulties and the set-backs.

No going back

But, inside the parliament building, there does seem to be growing nervousness about what a sudden shift in US policy could mean for the stability of Iraq.

Iraqi Foreign Minister Hoshiyar Zebari thinks a US withdrawal would be disastrous

"There are big changes coming here. Very big changes," says one MP as she scurries past, too busy to stop and chat.

Leaders in Iraq are starting to position themselves for what many see as an inevitable power struggle once American influence here starts to wane.

Military commanders are already talking about "post-surge Iraq". General Petraeus, the head of US forces here, says the priority is making sure hard fought gains can be "sustained, maintained and even built upon by Iraqi forces and political leaders".

The timing and speed of any US pull-out will be critical.

Hoshiyar Zebari, the Iraqi foreign minister, has already warned that a rapid withdrawal could lead to the "partition of Iraq and a regional war". He said the country might even "collapse altogether".

That fear is echoed across the political spectrum. Both Sunni and Shia politicians say it would be disastrous for the US to leave now.

"There would be chaos," says Mr Abdul Razzak. "It would be a great shock to the country. There could be a very severe civil war here."